Local Calling Guide

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Nisland, SD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
605-257 A BISNSDXADS0  1689 WEST RIVER COOPERATIVE TELEPHONE COMPANY 640      

Last updated: Tue, 07 Oct 2025 16:47:53 UTC

Sponsored by: ISP Telecom

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